<template>
  <div class="app-container">
    <h2 style="text-align: center">发布新课程</h2>
    <el-steps
      :active="1"
      process-status="wait"
      align-center
      style="margin-bottom: 40px"
    >
      <el-step title="填写课程基本信息" />
      <el-step title="创建课程大纲" />
      <el-step title="提交审核" />
    </el-steps>

    <el-form label-width="120px">
      <el-form-item label="课程标题">
        <el-input
          v-model="courseInfo.title"
          placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写"
        />
      </el-form-item>

      <!-- 所属分类：级联下拉列表 -->
      <!-- 一级分类 -->
      <el-form-item label="课程类别">
        <el-select
          v-model="courseInfo.subjectParentId"
          placeholder="一级分类"
          @change="subjectLevelOneChanged"
        >
          <el-option
            v-for="subject in subjectOneList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"
          />
        </el-select>
        <!-- 二级分类 -->
        <el-select v-model="courseInfo.subjectId" placeholder="二级分类">
          <el-option
            v-for="subject in subjectTwoList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"
          />
        </el-select>
      </el-form-item>
      <!-- 课程讲师 -->
      <el-form-item label="课程讲师">
        <el-select v-model="courseInfo.teacherId" placeholder="请选择">
          <el-option
            v-for="teacher in teacherList"
            :key="teacher.id"
            :label="teacher.name"
            :value="teacher.id"
          />
        </el-select>
      </el-form-item>
      <el-form-item label="总课时">
        <el-input-number
          :min="0"
          v-model="courseInfo.lessonNum"
          controls-position="right"
          placeholder="请填写课程的总课时数"
        />
      </el-form-item>
      <!-- 课程简介-->
      <el-form-item label="课程简介">
        <tinymce :height="300" v-model="courseInfo.description" />
      </el-form-item>
      <!-- 课程封面 -->
      <el-form-item label="课程封面">
        <el-upload
          :show-file-list="false"
          :on-success="handleAvatarSuccess"
          :before-upload="beforeAvatarUpload"
          :action="BASE_API + '/eduoss/fileoss'"
          class="avatar-uploader"
        >
          <img class="avatar" v-if="courseInfo.cover" :src="courseInfo.cover" />
        </el-upload>
      </el-form-item>

      <el-form-item>
        <el-button :disabled="saveBtnDisabled" type="primary" @click="next"
          >保存并下一步</el-button
        >
      </el-form-item>
    </el-form>
  </div>
</template>
<script>
import course from "@/api/edu/course";
import subject from "@/api/edu/subject";
import Tinymce from "@/components/Tinymce";

const defaultForm = {
  title: "",
  subjectId: "", //二级分类ID
  subjectParentId: "", //一级分类ID
  teacherId: "",
  lessonNum: 0,
  description: "",
  cover: "",
};
export default {
  components: { Tinymce },
  data() {
    return {
      saveBtnDisabled: false, // 保存按钮是否禁用
      courseInfo: defaultForm,
      BASE_API: process.env.BASE_API, // 接口API地址
      teacherList: [], // 讲师列表
      subjectOneList: [], //一级分类列表
      SubjectTwoList: [], //二级分类列表
      courseId: "",
    };
  },

  created() {
    console.log("info created");
    if (this.$route.params && this.$route.params.id) {
      this.courseId = this.$route.params.id;
      this.getInfo();
    } else {
      this.courseInfo = { ...defaultForm };
      this.getTeacherList();
      this.getOneSubject();
      this.courseInfo.cover =
        "https://gitee.com/jzhmcoo1/jzhmcoo1picrepo/raw/master/img/post.jpg";
    }
  },

  methods: {
    getInfo() {
      course.getCourseInfoById(this.courseId).then((response) => {
        this.courseInfo = response.data.courseInfoVo;
        //查询所有分类
        subject.getSubjectList().then((response) => {
          this.subjectOneList = response.data.list;
          //获取每个一级分类
          // 比较当前courseId和一级分类id的值
          for (let i = 0; i < this.subjectOneList.length; i++) {
            let oneSubject = this.subjectOneList[i];
            if (this.courseInfo.subjectParentId === oneSubject.id) {
              // 获取一级分类所有的二级分类
              this.subjectTwoList = oneSubject.children;
            }
          }
        });
        //获取教师列表
        this.getTeacherList();
      });
    },
    subjectLevelOneChanged(value) {
      //value就是一级分类id值
      //遍历所有的分类，包含一级和二级
      for (let i = 0; i < this.subjectOneList.length; i++) {
        //每个一级分类
        let oneSubject = this.subjectOneList[i];
        //判断：所有一级分类id 和 点击一级分类id是否一样
        if (value === oneSubject.id) {
          //从一级分类获取里面所有的二级分类
          this.subjectTwoList = oneSubject.children;
          //把二级分类id值清空
          this.courseInfo.subjectId = "";
        }
      }
    },
    getOneSubject() {
      subject.getSubjectList().then((response) => {
        this.subjectOneList = response.data.list;
      });
    },

    next() {
      console.log("next");
      this.saveBtnDisabled = true;
      if (!this.courseInfo.id) {
        this.saveData();
      } else {
        this.updateData();
      }
    },

    // 保存
    saveData() {
      course
        .addCourseInfo(this.courseInfo)
        .then((response) => {
          this.$message({
            type: "success",
            message: "添加课程信息成功!",
          });
          return response; // 将响应结果传递给then
        })
        .then((response) => {
          this.$router.push({
            path: "/course/chapter/" + response.data.courseId,
          });
        })
        .catch((response) => {
          this.$message({
            type: "error",
            message: response.message,
          });
        });
    },

    updateData() {
      course.updateCourseInfo(this.courseInfo).then((response) => {
        this.$message({
          type: "success",
          message: "修改课程信息成功!",
        });
        this.$router.push({ path: "/course/chapter/" + this.courseId });
      });
    },
    getTeacherList() {
      course.getTeacherList().then((response) => {
        this.teacherList = response.data.list;
      });
    },
    //上传之前调用的方法
    beforeAvatarUpload(file) {
      const isJPG = file.type === "image/jpeg";
      const isLt2M = file.size / 1024 / 1024 < 2;

      if (!isJPG) {
        this.$message.error("上传头像图片只能是 JPG 格式!");
      }
      if (!isLt2M) {
        this.$message.error("上传头像图片大小不能超过 2MB!");
      }
      return isJPG && isLt2M;
    },
    //上传封面成功调用的方法
    handleAvatarSuccess(res, file) {
      this.courseInfo.cover = res.data.url;
    },
  },
};
</script>
<style scoped>
.tinymce-container {
  line-height: 29px;
}

.avatar {
  max-height: 300px;
  max-width: 400px;
}
</style>

<style>
.app-container {
  max-width: 1200px;
}
</style>
